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Brigham · 19th Feb 2019, 10:29 am

The heaters were so arranged in order to ensure that the plug was removed when the heater was not in use.
I don't know when the rule came into force, but it was clearly a safety measure.
It allowed single-pole switching to be used safely. Otherwise, a cold heater, appearing to be 'dead', could have the firebars still live to the touch, even though not glowing, depending on which way round the mains plug happens to be.

19th Feb 2019, 10:29 am	#20
Brigham Octode Join Date: Mar 2006 Location: Co. Durham, UK. Posts: 1,117	Re: Another HMV Cavendish question The heaters were so arranged in order to ensure that the plug was removed when the heater was not in use. I don't know when the rule came into force, but it was clearly a safety measure. It allowed single-pole switching to be used safely. Otherwise, a cold heater, appearing to be 'dead', could have the firebars still live to the touch, even though not glowing, depending on which way round the mains plug happens to be.